Electrical connector



March 3, 1964 w. H. M KEE 3,

ELECTRICAL CONNECTOR Filed Dec. 26, 1961 IN VENTOR.

United States Patent 3,123,428 ELECTREUAL CONNETOR William H. McKee, West 'Coviua, Califi, assignor to United-Carr Fastener Corporation, Boston, Mass, a corporation of Delaware Filed Dec. 26, 1961, $er. No. 162,057 2 Claims. (Cl. 339-256) The present invention relates to an electrical connector and more particularly it relates to an electrical connector having an improved contact element.

Telephone installations, and the like frequently are provided such that a number of telephones may be installed conveniently in one area, for example, in an oflice area or building. Each of the separate circuits entering into such area are interconnected with the other circuits at a common point so that an interchange of signals between the respective circuits may be realized. With such interconnection each of the telephones installed in said area may receive and transmit messages on and between any one of the remaining circuits.

In providing such an installation it is necessary to connect each of the individual lines or circuits to each of the telephones installed in the area involved. This may be accomplished by running a line from the central point to each of the individual telephones and at each exchange or interconnection manually interconnecting each of the individual lines to the circuit for the individual telephones. It will be readily appreciated that this method is time consuming and particularly conducive to the introduction of errors in assembly.

The present invention is directed to the provision of an improved electrical connector that is especially suited for the rapid and accurate installation of multiple telephone systems. The connector involves a plug type adaptor having an improved connector element adapted for convenient installation within the connector body and further adapted to rapid, efiicient connection of the electrical conductors thereto.

It is therefore a general object of the present inven tion to provide an improved electrical connector as sembly having improved contact means adapted to pro vide for rapid, accurate installation of multiple telephone handsets, while abrogating the necessity for time consuming hand connection of the individual telephone circuits to the trunk line extending to each of the handsets.

It is an additional object of the present invention to provide an improved electrical connector assembly having improved contact elements each of the contact elements having a male contact portion at one end thereof, a female type contact portion at the other end thereof, and a wire receiving portion between the ends of the element.

It is a further object of the present invention to provide an improved electrical connector assembly having improved contact elements each of said contact elements being formed of electrically conductive spring-like material, said elements having male and female type contact portions disposed at opposite ends thereof and having a wire-receiving portion disposed intermediate the ends and formed continuously with said elements.

An additional object of the present invention is to provide an improved contact element for an electrical connector assembly said element being formed of electrically conductive spring-like material and having male and female type contact portions disposed at opposite ends thereof with a wire receiving portion intermediate the ends and spring biased away from the main body of the element to allow for insertion of a wire crimping tool.

The novel features which I believe to be characteristic of my invention are set forth with particularity in the appended claims. My invention itself, however, together 3,123,428 Patented Mar. 3, 1964 with further objects and advantages thereof, will best be understood by reference to the following description taken in connection with the accompanying drawings, in which:

FIGURE 1 is a schematic representation of a telephone circuit within which the connector of the present invention may be employed;

FIGURE 2 is an end elevation of the connector of the present invention;

FIGURE 3 is a side elevation of the connector of the present invention partly broken away to illustrate the mounting of the contact elements with respect to the connector;

FIGURE 4 is an end view of the connector of the present invention taken along lines 44 of FIGURE 3 illustrating the junction box on the connector;

FIGURE 5 is a top plan view of the contact element of the present invention; and

FIGURE 6 is a side elevational view of the contact element of the present invention.

Referring now more particularly to FIGURE 1 there is schematically represented a multi-handset telephone installation of the type in which the improved electrical connector of the present invention may be eifectively employed. A trunk line It? directly connected to external communication systems is electrically connected at a central area 12 from which area the individual circuits may be fed to the separate handsets within the limited area to be served. A plurality of conductors, represented by the line 14 in FIGURE 1, are fed to a terminal plug 16. The plug 16 is provided with contact element (described below) for each of the conductors presented thereto. An electrical connector 18, of the type disclosed herein in greater detail below, is plugged into the connector 16 in electrical association therewith to provide an electrical connection therebetween. A plurality of leads, represented by the line 2%, extend from the connector 18 to the handset 22 one lead extending therebetween for each of the circuits represented in the plurality of conductors 14. Thus, the handset 22 has a plurality of lines leading to the external circuits it? through the interconnection of the handset 22 therewith through the leads 20, the connectors 18 and 16 and the leads 14. An additional connector 24 is adapted to be received in the free face or" the connector 18 in electrical connection therewith. A plurality of electrical conductors are connected to the connector 24, one conductor being connected to each of the contact elements present therein. The leads connected to the connector 24 extend therefrom and are represented by the line 26 in FIGURE 1. Each of the conductors within the line 25 is connected to a contact element within the connector lea, the number of individual contact elements within said connector at least equalling the number of conductors presented thereto.

The connector 16a, in turn, may be electrically connected to connector 13a of the same type as connector 18, wherein a conductor representing each individual signal circuit within the system is interconnected between each of the individual contacts of the connector 18a and the handset, represented by the reference number 28, the interconnecting conductors benig represented by the line 39. Similarly, a connector 32 may be electrically joined to the connector 18a in the same fashion as connector 24 to extend therefrom and are represented by the line 26 in FIGURE 1. Each of the conductors within the line 26 is connected to a contact element within the connector Me, the number of individual contact elements within said connector at least equalling the number of conductors presented thereto.

The connector 15a, in turn, may be electrically connected to connector '18:: of the same type as connector greases 13, wherein a conductor representing each individual signal circuit within the system is interconnected between each of the individual contacts of the connector 18a and the handset, represented by the reference number 23, the interconnecting conductors being represented by the line 3%. Similarly, a connector 32 may be electrically joined to the connector 18a in the same fashion as connector 24 to extend the plurality of circuits to still another handset, and so on until the desired number of sets are all interconnected in whatever manner dictated by the requirements of the user. It can readily be seen that each of the handsets within the system is connected into the circuit in parallel with each of the other handsets within the system and that each set has access to each circuit presented to it in the electrically interconnecting circuitry.

The handsets illustrated by the numerals 22 and 2.8 may be quite distant, as noted by the interconnecting electrical circuits 26. Thus, the sets could be located at different desks in different ofiice areas. A further advantage may be achieved with the connector of the present invention when it is desired to place two or more handsets in close proximity and wherein the interconnecting junction box for the plurality of handsets must 'be shared by each of the sets within the immediate area. Such an arrangement is illustrated in FIGURE 1 wherein each of the circuit represented in line i l extends also, through line 34, t the connector 15!). The improved electrical connector of the present invention is electrically connected to the connector 16b as indicated at 1311 and the circuits 37 taken from this connector and fed to the hand set 36. One such connector 13 is required for each handset to be serviced. Thus, if a second handset is to be serviced from the same connector 16b 21 second connector 180 is electrically connected to the preceding connector, in this case connector 1817, and the circuits it? for the handset 3% taken from the connector 1811, in the manner to be described below. As additional handsets are required in the immediate area, additional connectors 18 are added, one for each handset required.

The improved electrical connector 8 of the present invention is described in connection with FIGURES 2, 3, and 4. A two-part separated metal casing, indicated generally at 4-1, is comprised of two half-portions 42 and 44, respectively. Each of the half-portions 42 and 44 has a mating projection 46 and 48, respectively, thereon. Further projections 50 and 52 are provided on the same side of the body portions 421 and 4 respectively, as the projections 46 and 48. It will be noted that when the separated portions 42 and 44 are joined in mating relation, as shown in FIGURE 4, the projections 46, 38, t? and 52 define an interrupted circular portion having an opening 54 therebetween.

The body portion 42 has a further projection 56 thereon said body portion 42 adapted to be positioned in mating relation with the projection on the body portion 4 The projection 58 has an opening therein (not shown) to receive a retaining member 6i in slidable relation therewith. 'ihe projection 56 has a threaded opening (not shown) therein in mating coaxial relation with the opening in the projection 53. The retaining member on is inserted into the opening in projection 58 and is threaded into the opening in projection 56 to thereby provide a means of fastening the two-part separate body portion into a joined unit.

A pair of adjusting members 62 and 64 are cooperatively associated with the projections 46 and 5d, and 43 and 52, respectively, to provide means for adjusting the size of the opening 54 therebetween.

An insulating body 66 of phenolic resin, or some other suitable insulating material, is disposed within the twopart casing 41 and adapted to be confined therein when the casing is in joined relation. The insulating body is provided with a plurality of open shafts 68, said shafts 68 extending entirely through the insulating body as to define contact element receiving openings. A central open area 79 is defined Within the insulating body 66 proper, for reasons set forth below. The shaft 63 is of irregular, shaped construction as it extends through the insulating body to provide a convenient, restrictive receptacle for the contact element. It will be noted that the shaft 68, at one end thereof is substantial y square in cross section, as indicated at 72. A flat, shallow rectangular opening 74 is presented within the outlines defined by the square 0pen ing 72 with the ends of the rectangle extending slightly beyond the opposite sides of the square opening 72. The opening "74' thus is superimposed upon the opening 72 to present a generally cross-shaped cross sectional configuration. A barrier 76 is interposed within the shaft opening 68 adjacent the opposite terminal thereof. Said barrier '76 is adapted to engage mating projections on the contact element (described below) to confine the contact elernent within the opening 68 once it is inserted therein.

The contact element, indicated generally at St), FIG- URES 5 and 6, is formed from a unitary electrically conductive member. The metal from which the contact element an is formed, in addition to desired electrical conduc tivity characteristics, has a spring-like character suitable to define appropriate physical characteristics for the female-type contact portion 32 of the contact element and to spring (bias the element into restrictive relation within the shaft as when inserted therein.

The contact is folded, as indicated generally at 84, said portion defining along its folded length, a male-type prong contact portion. The fiexural characteristics, or yield point of the metal, of course, are exceeded in the formation of the folded portion so that the fold becomes permanent.

One free end of the metal strip of the contact element 80 is disposed perpendicularly to the plane of the main body portion of the element to define the female-type contact portion 82. The female-type contact portion 82 includes a pair of flexible spring-like prongs 86 and 38 adapted to be flexed into greater spaced relation upon insertion of an electrical prong-type contact therebetween (not shown) the flexural characteristics of the prongs further adapted to bias the prongs 86 and 88 toward the inserted prong and into electrical conductive relation therewith. Each of the prongs 8t: and 88 is integrally attached to the base portion 9d. A spring tab 92 is punched out and bent slightly outwardly from the base portion 9% to form a locking tab for the contact element 8% when the element is inserted into the open shaft 68 of he insulating body 66. A shoulder 94 is formed on the base portion @d and provides a stop member to position the contact element within the open shaft, as described below. A second shoulder d6 is formed on the main body portion of the contact element 6d and defines an additional stop member to facilitate positive positioning of the element 86 within the insulating body.

The other free end of the metal strip of the contact element St} defines a conductor receiving portion, indicated generally at filth. The portion 1% is spring biased away from the main body portion of the element 80 to thus provide room for introduction of an appropriate wire fastening or crimping tool about the portion 1% to facilitate attachment of a conductor to said portion. The conductor receiving portion is generally U-shaped in cross section and has a pair of upstanding tabs 102 and 1% in spaced relation along one side thereof with a tab 106 disposed along the opposite side of the U-shaped channel. The insulation may be stripped from the end of the conductor (not shown) to be affixed within the conductor receiving portion lliili to assure electrical contact with the contact element 89. Alternatively, insulation piercing tabs 103 and W5 may be formed at the base of the conductor receiving portion 10%. Said tabs 103 and N5 are adapted to pierce the insulating layer over the conductor and establish electrical contact therewith.

The contact element lid is mounted within the insulating body 66 of the connector 18, as indicated in FIGURE 3. Preferably, the insulating body 66 is of two-part construction having a male prong element receiving portion 66a and a female-type contact receiving portion 66b. Said portions 664: and 66b are held in spaced relation by spacers (not shown) or by other conventional means to define the central open area 70. Each of the contact element receiving portions 66a and 66b, respectively, have aligned contact receiving passages 66c and 66d, respectively. The contact receiving passage 660 is adapted to receive the male or prong portion of the contact element, as described below. The contact receiving passage 66d is adapted to receive the female portion of the contact element noted in greater detail below. The contact element 80 may first be inserted into the female receiving portion 66b with, of course, the female contact portion 82 of the contact 80 being inserted therein. The female portion 82 is inserted into the insulating portion 66b from the side 67 of said insulating portion. The female contact 82 passes through an opening in the insulating portion 66b defined within the barrier 76. The spring tab 92 is pressed into the main body portion of the base portion 99 to permit the element 80 to pass through said opening. After the spring tab 92 has passed beyond the barrier 76 it is biased outwardly to prevent withdrawal of the contact element 80 from the open shaft 68. The shoulder 96 of the main body portion of the contact element 88 abuts against the barrier 76 at substantially the same point that the spring tab 92 completely passes through the opening in the barrier 76 so that further insertion of the element 80 into the shaft 68 is prevented. Once the spring tab 92 has passed through the opening in the barrier 76 and sprung outwardly it can readily be seen that the contact element 80 may not be moved either Way within the shaft 68, movement being inhibited in one direction by the spring tab 92 and in the other direction by the shoulder 96.

Preferably, the conductor 108 is inserted into the conductor receiving portion 188 of the contact element 80 prior to insertion of the contact element into the insulating body of the electrical connector 18. After electrical connection of the conductors 108 to each of the contact elements 80 the male portion of the contact element is inserted into the contact receiving passage 66c. Insertion of the contact element 80 into passage 66c serves to urge the conductor receiving portion 100 and the main body of the contact element 80' into intimate adjacent relation, the portion 100 finally coming to rest upon the main body portion of the contact element 88 in aligned relation therewith. The conductors are fastened to the portions 100 by laying the conductor within the generally U-shaped channel; inserting the wire crimping tool over the portion 100; and then folding the tabs 102, 104 and 186 down over the conductor to afiix it within the channel.

When all of the contact elements 80 have been inserted into the female-receiving portion 66b of the in sulating body 66 the male prong-receiving portion 66a of the insulating body is inserted in telescoped relation over the prong portions 84 of the elements 80'. The entire split assembly is then assembled and fixed in joined relation.

While I have shown and described a specific embodiment of the present invention it will, of course, be understood that other modifications and alternative constructions may be used without departing from the true spirit and scope of this invention. I therefore intend by the appended claims to cover all such modifications and alternative constructions as fall within their true spirit and scope.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. An improved contact element for an electrical connector of the type having an insulating body with a plurality of contact element receiving shafts therein, comprising:

a continuously formed spring-like member folded along a portion of its length to define a prong portion with two free ends, one of said free ends being formed to define a female receptacle having spaced spring biased prongs, the plane of the female receptacle portion being disposed perpendicularly to the plane of the main body portion, the other of said free ends being formed to define a conductor receiving portion and terminating at a point intermediate the terminals of the male and female portions, respectively, said conductor receiving portion being formed to define a fiat base portion having a plurality of spaced upstanding tabs along either side thereof, said tabs adapted, when in use, to be folded over a conductor which is inserted therein to confine said conductor within the conductor receiving portion, said conductor receiving portion providing means of electrical connection of said contact element to a conductor.

2. An improved contact element for an electrical connector of the type having an insulated body with a plurality of contact element receiving shafts therein, comprising:

a continuously formed spring-like member folded along a portion of its length to define a prong portion with two free ends, one of said free ends being formed to define a female receptacle having spaced spring biased prongs, the other of said free ends being formed to define a conductor receiving portion and terminating at a point intermediate said female receptacle and said prong portion, said conductor receiving portion having attaching elements engageable over a conductor which is inserted therein to confine said conductor within the conductor receiving portion, said conductor receiving portion providing means of electrical connection of said contact element to a conductor.

References Cited in the file of this patent UNITED STATES PATENTS 

2. AN IMPROVED CONTACT ELEMENT FOR AN ELECTRICAL CONNECTOR OF THE TYPE HAVING AN INSULATED BODY WITH A PLURALITY OF CONTACT ELEMENT RECEIVING SHAFTS THEREIN, COMPRISING: A CONTINUOUSLY FORMED SPRING-LIKE MEMBER FOLDED ALONG A PORTION OF ITS LENGTH TO DEFINE A PRONG PORTION WITH TWO FREE ENDS, ONE OF SAID FREE ENDS BEING FORMED TO DEFINE A FEMALE RECEPTACLE HAVING SPACED SPRING BIASED PRONGS, THE OTHER OF SAID FREE ENDS BEING FORMED TO DEFINE A CONDUCTOR RECEIVING PORTION AND TERMINATING AT A POINT INTERMEDIATE SAID FEMALE RECEPTACLE AND SAID PRONG PORTION, SAID CONDUCTOR RECEIVING PORTION HAVING ATTACHING ELEMENTS ENGAGEABLE OVER A CONDUCTOR WHICH IS INSERTED THEREIN TO CONFINE SAID CONDUCTOR WITHIN THE CONDUCTOR RECEIVING PORTION, SAID CONDUCTOR RECEIVING PORTION PROVIDING MEANS OF ELECTRICAL CONNECTION OF SAID CONTACT ELEMENT TO A CONDUCTOR. 